Mechanisms of Dermatophyte Invasion on New Zealand Rabbit Skin Models

Abstract

Dermatophytosis is a dermatophyte fungi infection most commonly found in animals and humans. The first step of infection is started from the attachment of arthroconidium into stratum corneum. The attachment of fungi to the host cell is mediated by fungi adhesin and its interaction with the host receptor. The objective of this research was to develop the infection model of Microsporum gypseum and Microsporum canis by inoculating the macroconidia intradermally on the rabbit model. The macroconidia collection method from culture media was re-visualized as fungi ultrastructure using scanning electron microscopy (SEM). Skin lesion analysis was measured from clinical changes of the skin based on primary dermatophytosis signs such as circular alopecia with erythema and squamosal. Clinical confirmation test was done via skin sampling followed by histopathological examination using Methenamine Silver - Grocott's (GMS) staining. As a result of this research, the in vivo infection model through direct infection of macroconidia applied intradermally was very effective in improving the direct infection to the invasion phase on the skin. This model confirmed the epidermal differentiation process and skin permeability showed primary lesion within 2 hours and aggravated up to 6 hours after inoculation. In conclusion, macroconidium is a potential source of infection to induce the dermatophytosis model and the severity of primary injection correlated with duration and the scale of clinical symptoms exhibited. This is a promising model for further research on the mechanism involved in dermatophyte infection.